<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      let a = 100;
      let b = 200;
      console.log("a=", a, "b=", b); //100,200
      [b, a] = [a, b]; //[100,200]
      console.log("a=", a, "b=", b); //200,100
    </script>
  </body>
</html>
